In terms of macrolithotypes and microlithotypes, the petrographic composition was determined on column samples of Permian Seam 2 and Carboniferous Seam 9(2) from the Xingtai Coalfield, China. The macrolithotypes are c...In terms of macrolithotypes and microlithotypes, the petrographic composition was determined on column samples of Permian Seam 2 and Carboniferous Seam 9(2) from the Xingtai Coalfield, China. The macrolithotypes are classified into bright coal (B), banded bright coal (BB), banded coal (BC),banded dull coal (BD), dull coal (D) and fibrous coal (F). The lithotypes are dominated by BD and D in Seam 2, and BB in Seam 9(2).Microlithotypes are dominated by inertite and durite in Seam 2 and by vitrite in Seam 9(2). Eight microlithotypes were selected as indicators of peat-forming environments. Two triangle diagrams were drawn based on the indicators in order to explicate the peat-forming environments of Permian Seam 2 and Carboniferous Seam 9(2). The results indicate that the peat of Carboniferous Seam 9(2) was formed dominantly in wet swamps, whereas tbe peat of Permian Seam 2 formed dominantly in dry and wet swamps. These results are agree with the regional geology, that is, the peat of Carboniferous Seam 9(2) was formed in a transition zone and the peat of Permian Seam 2 formed in an upper delta zone.The climate of the peat-forming time for Permian Seam 2 was drier than that for Carboniferous.展开更多
文摘In terms of macrolithotypes and microlithotypes, the petrographic composition was determined on column samples of Permian Seam 2 and Carboniferous Seam 9(2) from the Xingtai Coalfield, China. The macrolithotypes are classified into bright coal (B), banded bright coal (BB), banded coal (BC),banded dull coal (BD), dull coal (D) and fibrous coal (F). The lithotypes are dominated by BD and D in Seam 2, and BB in Seam 9(2).Microlithotypes are dominated by inertite and durite in Seam 2 and by vitrite in Seam 9(2). Eight microlithotypes were selected as indicators of peat-forming environments. Two triangle diagrams were drawn based on the indicators in order to explicate the peat-forming environments of Permian Seam 2 and Carboniferous Seam 9(2). The results indicate that the peat of Carboniferous Seam 9(2) was formed dominantly in wet swamps, whereas tbe peat of Permian Seam 2 formed dominantly in dry and wet swamps. These results are agree with the regional geology, that is, the peat of Carboniferous Seam 9(2) was formed in a transition zone and the peat of Permian Seam 2 formed in an upper delta zone.The climate of the peat-forming time for Permian Seam 2 was drier than that for Carboniferous.
